new weapon to fight cancer

1. British scientists are preparing to launch trials of a radical new way to fight cancer, which kills tumours by infecting them with viruses like the common cold.

2. If successful, virus therapy could eventually form a third pillar alongside radiotherapy and chemotherapy in the standard arsenal against cancer, while avoiding some of the debilitating side-effects.

3. Leonard Seymour, a professor of gene therapy at Oxford University, who has been working on the virus therapy with colleagues in London and the US, will lead the trials later this year. Cancer Research UK said yesterday that it was excited by the potential of Prof Seymour’s pioneering techniques.

4. One of the country’s leading geneticists, Prof Seymour has been working with viruses that kill cancer cells directly, while avoiding harm to healthy tissue. "In principle, you’ve got something which could be many times more effective than regular chemotherapy," he said.

5. Cancer-killing viruses exploit the fact that cancer cells suppress the body’s local immune system. "If a cancer doesn’t do that, the immune system wipes it out. If you can get a virus into a tumour, viruses find them a very good place to be because there’s no immune system to stop them replicating. You can regard it as the cancer’s Achilles’ heel."

6. Only a small amount of the virus needs to get to the cancer. "They replicate, you get a million copies in each cell and the cell bursts and they infect the tumour cells adjacent and repeat the process," said Prof Seymour.

7. Preliminary research on mice shows that the viruses work well on tumours resistant to standard cancer drugs. "It’s an interesting possibility that they may have an advantage in killing drug-resistant tumours, which could be quite different to anything we’ve had before."

8. Researchers have known for some time that viruses can kill tumour cells and some aspects of the work have already been published in scientific journals. American scientists have previously injected viruses directly into tumours but this technique will not work if the cancer is inaccessible or has spread throughout the body.

9. Prof Seymour’s innovative solution is to mask the virus from the body’s immune system, effectively allowing the viruses to do what chemotherapy drugs do - spread through the blood and reach tumours wherever they are. The big hurdle has always been to find a way to deliver viruses to tumours via the bloodstream without the body’s immune system destroying them on the way.

10. "What we’ve done is make chemical modifications to the virus to put a polymer coat around it - it’s a stealth virus when you inject it," he said.

11. After the stealth virus infects the tumour, it replicates, but the copies do not have the chemical modifications. If they escape from the tumour, the copies will be quickly recognised and mopped up by the body’s immune system.

12. The therapy would be especially useful for secondary cancers, called metastases, which sometimes spread around the body after the first tumour appears. "There’s an awful statistic of patients in the west ... with malignant cancers; 75% of them go on to die from metastases," said Prof Seymour.

13. Two viruses are likely to be examined in the first clinical trials: adenovirus, which normally causes a cold-like illness, and vaccinia, which causes cowpox and is also used in the vaccine against smallpox. For safety reasons, both will be disabled to make them less pathogenic in the trial, but Prof Seymour said he eventually hopes to use natural viruses.

14. The first trials will use uncoated adenovirus and vaccinia and will be delivered locally to liver tumours, in order to establish whether the treatment is safe in humans and what dose of virus will be needed. Several more years of trials will be needed, eventually also on the polymer-coated viruses, before the therapy can be considered for use in the NHS. Though the approach will be examined at first for cancers that do not respond to conventional treatments, Prof Seymour hopes that one day it might be applied to all cancers.

Questions 1-6

Do the following statements agree with the information given in the reading passage? For questions 1-6 write

TRUE if the statement agrees with the information

FALSE if the statement contradicts the information

NOT GIVEN if there is no information on this in the passage

1.Virus therapy, if successful, has an advantage in eliminating side-effects.

2.Cancer Research UK is quite hopeful about Professor Seymour’s work on the virus therapy.

3.Virus can kill cancer cells and stop them from growing again.

4.Cancer’s Achilles’ heel refers to the fact that virus may stay safely in a tumor and replicate.

5.To infect the cancer cells, a good deal of viruses should be injected into the tumor.

6.Researches on animals indicate that virus could be used as a new way to treat drug-resistant tumors.

Question 7-9

Based on the reading passage, choose the appropriate letter from A-D for each answer.

7.Information about researches on viruses killing tumor cells can be found

(A) on TV

(B) in magazines

(C) on internet

(D) in newspapers

8.To treat tumors spreading out in body, researchers try to

(A) change the body’ immune system

(B) inject chemotherapy drugs into bloodstream.

(C) increase the amount of injection

(D) disguise the viruses on the way to tumors.

9.When the chemical modified virus in tumor replicates, the copies

(A) will soon escape from the tumor and spread out.

(B) will be wiped out by the body’s immune system.

(C) will be immediately recognized by the researchers.

(D) will eventually stop the tumor from spreading out.

Questions 10-13

Complete the sentences below. Choose your answers from the list of words. You can only use each word once.

NB There are more words in the list than spaces so you will not use them all.

In the first clinical trials, scientists will try to ……10…… adenovirus and vaccinia, so both the viruses will be less pathogenic than the ……11…….These uncoated viruses will be applied directly to certain areas to confirm safety on human beings and the right ……12…… needed. The experiments will firstly be ……13……to the treatment of certain cancers

1 There's a dimmer switch inside the sun that causes its brightness to rise and fall on timescales of around 100,000 years - exactly the same period as between ice ages on Earth. So says a physicist who has created a computer model of our star's core.

2 Robert Ehrlich of George Mason University in Fairfax, Virginia, modelled the effect of temperature fluctuations in the sun's interior. According to the standard view, the temperature of the sun's core is held constant by the opposing pressures of gravity and nuclear fusion. However, Ehrlich believed that slight variations should be possible.

3 He took as his starting point the work of Attila Grandpierre of the Konkoly Observatory of the Hungarian Academy of Sciences. In 2005, Grandpierre and a collaborator, Gábor ágoston, calculated that magnetic fields in the sun's core could produce small instabilities in the solar plasma. These instabilities would induce localised oscillations in temperature.

4 Ehrlich's model shows that whilst most of these oscillations cancel each other out, some reinforce one another and become long-lived temperature variations. The favoured frequencies allow the sun's core temperature to oscillate around its average temperature of 13.6 million kelvin in cycles lasting either 100,000 or 41,000 years. Ehrlich says that random interactions within the sun's magnetic field could flip the fluctuations from one cycle length to the other.

5 These two timescales are instantly recognisable to anyone familiar with Earth's ice ages: for the past million years, ice ages have occurred roughly every 100,000 years. Before that, they occurred roughly every 41,000 years.

6 Most scientists believe that the ice ages are the result of subtle changes in Earth's orbit, known as the Milankovitch cycles. One such cycle describes the way Earth's orbit gradually changes shape from a circle to a slight ellipse and back again roughly every 100,000 years. The theory says this alters the amount of solar radiation that Earth receives, triggering the ice ages. However, a persistent problem with this theory has been its inability to explain why the ice ages changed frequency a million years ago.

7 "In Milankovitch, there is certainly no good idea why the frequency should change from one to another," says Neil Edwards, a climatologist at the Open University in Milton Keynes, UK. Nor is the transition problem the only one the Milankovitch theory faces. Ehrlich and other critics claim that the temperature variations caused by Milankovitch cycles are simply not big enough to drive ice ages.

8 However, Edwards believes the small changes in solar heating produced by Milankovitch cycles are then amplified by feedback mechanisms on Earth. For example, if sea ice begins to form because of a slight cooling, carbon dioxide that would otherwise have found its way into the atmosphere as part of the carbon cycle is locked into the ice. That weakens the greenhouse effect and Earth grows even colder.

9 According to Edwards, there is no lack of such mechanisms. "If you add their effects together, there is more than enough feedback to make Milankovitch work," he says. "The problem now is identifying which mechanisms are at work." This is why scientists like Edwards are not yet ready to give up on the current theory. "Milankovitch cycles give us ice ages roughly when we observe them to happen. We can calculate where we are in the cycle and compare it with observation," he says. "I can't see any way of testing [Ehrlich's] idea to see where we are in the temperature oscillation."

10 Ehrlich concedes this. "If there is a way to test this theory on the sun, I can't think of one that is practical," he says. That's because variation over 41,000 to 100,000 years is too gradual to be observed. However, there may be a way to test it in other stars: red dwarfs. Their cores are much smaller than that of the sun, and so Ehrlich believes that the oscillation periods could be short enough to be observed. He has yet to calculate the precise period or the extent of variation in brightness to be expected.

11 Nigel Weiss, a solar physicist at the University of Cambridge, is far from convinced. He describes Ehrlich's claims as "utterly implausible". Ehrlich counters that Weiss's opinion is based on the standard solar model, which fails to take into account the magnetic instabilities that cause the temperature fluctuations.

Questions 1-4

Complete each of the following statements with One or Two names of the scientists from the box below.

Write the appropriate letters A-E in boxes 1-4 on your answer sheet.

A. Attila Grandpierre

B. Gábor ágoston

C. Neil Edwards

D. Nigel Weiss

E. Robert Ehrlich

1. ...claims there a dimmer switch inside the sun that causes its brightness to rise and fall in periods as long as those between ice ages on Earth.

2. ...calculated that the internal solar magnetic fields could produce instabilities in the solar plasma.

3. ...holds that Milankovitch cycles can induce changes in solar heating on Earth and the changes are amplified on Earth.

4. ...doesn't believe in Ehrlich's viewpoints at all.

Questions 5-9

Do the following statements agree with the information given in the reading passage?

In boxes 5-9 on your answer sheet write

TRUE if the statement is true according to the passage

FALSE if the statement is false according to the passage

NOT GIVEN if the information is not given in the passage

5. The ice ages changed frequency from 100,000 to 41,000 years a million years ago.

6. The sole problem that the Milankovitch theory can not solve is to explain why the ice age frequency should shift from one to another.

7. Carbon dioxide can be locked artificially into sea ice to eliminate the greenhouse effect.

8. Some scientists are not ready to give up the Milankovitch theory though they haven't figured out which mechanisms amplify the changes in solar heating.

9. Both Edwards and Ehrlich believe that there is no practical way to test when the solar temperature oscillation begins and when ends.

Questions 10-14

Complete the notes below.

Choose one suitable word from the Reading Passage above for each answer.

Write your answers in boxes 10-14 on your answer sheet.

The standard view assumes that the opposing pressures of gravity and nuclear fusions hold the temperature ...10...in the sun's interior, but the slight changes in the earth's ...11... alter the temperature on the earth and cause ice ages every 100,000 years. A British scientist, however, challenges this view by claiming that the internal solar magnetic ...12... can induce the temperature oscillations in the sun's interior. The sun's core temperature oscillates around its average temperature in ...13... lasting either 100,000 or 41,000 years. And the ...14... interactions within the sun's magnetic field could flip the fluctuations from one cycle length to the other, which explains why the ice ages changed frequency a million years ago.

Intheearlieststagesofman'sdevelopmenthehadnomoreneedofmoneythananimalshave.Hewascontentwithverysimpleformsofshelter,madehisownroughtoolsandweaponsandcouldprovidefoodandclothingforhimselfandhisfamilyfromnaturalmaterialsaroundhim.Ashebecamemorecivilized,however,hebegantowantbettershelter,moreefficienttoolsandweapons,andmorecomfortableandmorelastingclothingthancouldbeprovidedbyhisownneighborhoodorbytheworkofhisownunskilledhands.Forthesethingshehadtoturntotheskilledpeoplesuchassmiths,leatherworkersorcarpenters.Itwasthenthatthequestionofpaymentarose.

Atfirsthegotwhathewantedbyasimpleprocessofexchange.Thesmithwhohadnotthetimetolookafterlandorcattlewasgladtotakemeatorgrainfromthefarmerinexchangeforanaxeoraplough.Butasmoreandmoregoodswhichhadnofixedexchangevaluecameonthemarket,exchangebecametoocomplicatedtobesatisfactory.Anotherproblemarosewhenthosewhomadethingswantedtogetstocksofwoodorleather,oriron,buthadnothingtoofferinexchangeuntiltheirfinishedgoodswereready.Thusthedifficultiesofexchangeledbydegreestotheinventionofmoney.Insomecountrieseasilyhandledthingslikeseedsorshellsweregivenacertainvalueandthefarmer,insteadofpayingthesmithforanewaxebygivinghimsomemeatorgrain,gavehimsomanyshells.Ifthesmithhadanyshellsleftwhenhehadboughthisfood,hecouldgetstocksoftherawmaterialsofhistrade.Insomecountriesquitelargethingssuchascowsorcamelsorevenbigflatstoneswereusedfortrade.Later,piecesofmetal,bearingvaluesaccordingtotherarityofthemetalandthesizeofthepieces,orcoinswereused.Moneyasweknowithadarrived.

1.Exchangeofgoodsbecamedifficultbecause_________.

Amanbecamemorecivilized

Bsmithsbegantolookafterlandorcattleintheirsparetime

Cmoreandmoregoodswhichhadnofixedexchangealuescametothemarker

Dfarmershadn'tenoughgrainormeattoprovidefor

skilledworkers

2.Moneywasnotuseduntil_______.

Apaperwasinvented

Bpeoplepracticedasimpleprocessofexchange

CnothingcouldbeofferedinexchangeDtheexchangeofonethingforanotherbecametoocomplicated

3.Thebesttitleforthispassageis_____.

AWhatismoney

BWhataremoney'sfunctions.

CTheimportanceofmoney

DThebeginningofmoney

-----Tinahadnothingforbreakfast,____________she?

-----_____________.Shehadsomebreadandmilk.

1There'sadimmerswitchinsidethesunthatcausesitsbrightnesstoriseandfallontimescalesofaround100,000years-exactlythesameperiodasbetweeniceagesonEarth.Sosaysaphysicistwhohascreatedacomputermodelofourstar'score.

2RobertEhrlichofGeorgeMasonUniversityinFairfax,Virginia,modelledtheeffectoftemperaturefluctuationsinthesun'sinterior.Accordingtothestandardview,thetemperatureofthesun'scoreisheldconstantbytheopposingpressuresofgravityandnuclearfusion.However,Ehrlichbelievedthatslightvariationsshouldbepossible.

3HetookashisstartingpointtheworkofAttilaGrandpierreoftheKonkolyObservatoryoftheHungarianAcademyofSciences.In2005,Grandpierreandacollaborator,Gáborágoston,calculatedthatmagneticfieldsinthesun'scorecouldproducesmallinstabilitiesinthesolarplasma.Theseinstabilitieswouldinducelocalisedoscillationsintemperature.

4Ehrlich'smodelshowsthatwhilstmostoftheseoscillationscanceleachotherout,somereinforceoneanotherandbecomelong-livedtemperaturevariations.Thefavouredfrequenciesallowthesun'scoretemperaturetooscillatearounditsaveragetemperatureof13.6millionkelvinincycleslastingeither100,000or41,000years.Ehrlichsaysthatrandominteractionswithinthesun'smagneticfieldcouldflipthefluctuationsfromonecyclelengthtotheother.

5ThesetwotimescalesareinstantlyrecognisabletoanyonefamiliarwithEarth'siceages:forthepastmillionyears,iceageshaveoccurredroughlyevery100,000years.Beforethat,theyoccurredroughlyevery41,000years.

6MostscientistsbelievethattheiceagesaretheresultofsubtlechangesinEarth'sorbit,knownastheMilankovitchcycles.OnesuchcycledescribesthewayEarth'sorbitgraduallychangesshapefromacircletoaslightellipseandbackagainroughlyevery100,000years.ThetheorysaysthisalterstheamountofsolarradiationthatEarthreceives,triggeringtheiceages.However,apersistentproblemwiththistheoryhasbeenitsinabilitytoexplainwhytheiceageschangedfrequencyamillionyearsago.

7"InMilankovitch,thereiscertainlynogoodideawhythefrequencyshouldchangefromonetoanother,"saysNeilEdwards,aclimatologistattheOpenUniversityinMiltonKeynes,UK.NoristhetransitionproblemtheonlyonetheMilankovitchtheoryfaces.EhrlichandothercriticsclaimthatthetemperaturevariationscausedbyMilankovitchcyclesaresimplynotbigenoughtodriveiceages.

8However,EdwardsbelievesthesmallchangesinsolarheatingproducedbyMilankovitchcyclesarethenamplifiedbyfeedbackmechanismsonEarth.Forexample,ifseaicebeginstoformbecauseofaslightcooling,carbondioxidethatwouldotherwisehavefounditswayintotheatmosphereaspartofthecarboncycleislockedintotheice.ThatweakensthegreenhouseeffectandEarthgrowsevencolder.

9AccordingtoEdwards,thereisnolackofsuchmechanisms."Ifyouaddtheireffectstogether,thereismorethanenoughfeedbacktomakeMilankovitchwork,"hesays."Theproblemnowisidentifyingwhichmechanismsareatwork."ThisiswhyscientistslikeEdwardsarenotyetreadytogiveuponthecurrenttheory."Milankovitchcyclesgiveusiceagesroughlywhenweobservethemtohappen.Wecancalculatewhereweareinthecycleandcompareitwithobservation,"hesays."Ican'tseeanywayoftesting[Ehrlich's]ideatoseewhereweareinthetemperatureoscillation."

10Ehrlichconcedesthis."Ifthereisawaytotestthistheoryonthesun,Ican'tthinkofonethatispractical,"hesays.That'sbecausevariationover41,000to100,000yearsistoogradualtobeobserved.However,theremaybeawaytotestitinotherstars:reddwarfs.Theircoresaremuchsmallerthanthatofthesun,andsoEhrlichbelievesthattheoscillationperiodscouldbeshortenoughtobeobserved.Hehasyettocalculatethepreciseperiodortheextentofvariationinbrightnesstobeexpected.

11NigelWeiss,asolarphysicistattheUniversityofCambridge,isfarfromconvinced.HedescribesEhrlich'sclaimsas"utterlyimplausible".EhrlichcountersthatWeiss'sopinionisbasedonthestandardsolarmodel,whichfailstotakeintoaccountthemagneticinstabilitiesthatcausethetemperaturefluctuations.

Questions1-4

CompleteeachofthefollowingstatementswithOneorTwonamesofthescientistsfromtheboxbelow.

WritetheappropriatelettersA-Einboxes1-4onyouranswersheet.

A.AttilaGrandpierre

B.Gáborágoston

C.NeilEdwards

D.NigelWeiss

E.RobertEhrlich

1....claimsthereadimmerswitchinsidethesunthatcausesitsbrightnesstoriseandfallinperiodsaslongasthosebetweeniceagesonEarth.

2....calculatedthattheinternalsolarmagneticfieldscouldproduceinstabilitiesinthesolarplasma.

3....holdsthatMilankovitchcyclescaninducechangesinsolarheatingonEarthandthechangesareamplifiedonEarth.

4....doesn'tbelieveinEhrlich'sviewpointsatall.

Questions5-9

Dothefollowingstatementsagreewiththeinformationgiveninthereadingpassage?

Inboxes5-9onyouranswersheetwrite

TRUEifthestatementistrueaccordingtothepassage

FALSEifthestatementisfalseaccordingtothepassage

NOTGIVENiftheinformationisnotgiveninthepassage

5.Theiceageschangedfrequencyfrom100,000to41,000yearsamillionyearsago.

6.ThesoleproblemthattheMilankovitchtheorycannotsolveistoexplainwhytheiceagefrequencyshouldshiftfromonetoanother.

7.Carbondioxidecanbelockedartificiallyintoseaicetoeliminatethegreenhouseeffect.

8.SomescientistsarenotreadytogiveuptheMilankovitchtheorythoughtheyhaven'tfiguredoutwhichmechanismsamplifythechangesinsolarheating.

9.BothEdwardsandEhrlichbelievethatthereisnopracticalwaytotestwhenthesolartemperatureoscillationbeginsandwhenends.

Questions10-14

Completethenotesbelow.

ChooseonesuitablewordfromtheReadingPassageaboveforeachanswer.

Writeyouranswersinboxes10-14onyouranswersheet.

Thestandardviewassumesthattheopposingpressuresofgravityandnuclearfusionsholdthetemperature...10...inthesun'sinterior,buttheslightchangesintheearth's...11...alterthetemperatureontheearthandcauseiceagesevery100,000years.ABritishscientist,however,challengesthisviewbyclaimingthattheinternalsolarmagnetic...12...caninducethetemperatureoscillationsinthesun'sinterior.Thesun'scoretemperatureoscillatesarounditsaveragetemperaturein...13...lastingeither100,000or41,000years.Andthe...14...interactionswithinthesun'smagneticfieldcouldflipthefluctuationsfromonecyclelengthtotheother,whichexplainswhytheiceageschangedfrequencyamillionyearsago.